It is well known to construct walls and other structures with stone and bricks. Natural stone structures are constructed by cutting and fitting irregularly sized and shaped stones. The work requires a skilled stonemason to select, cut, and fit the stone. It is labor intensive, and accordingly expensive. Custom built natural stone structures, however, are very attractive and desirable.
It is also well known to construct walls and other structures with manufactured building units such as bricks and concrete blocks (CMU). Such units can be made from concrete, brick, or various other materials. Units are conventionally provided in geometric shapes, and are typically are laid in repeating patterns. It is desirable to construct walls, such as retaining walls, and other structures that have a unique appearance and are aesthetically pleasing. It is also desirable to construct such structures easily and economically from manufactured units.